The present invention relates generally to fluid control valves. More particularly, the present invention concerns a diverter valve which is bodily movable and which has a pair of check valves.
In the past it has been known to use a valve arrangement to control the flow of cooking oil between a reservoir chamber and a cooking chamber. See for example, U.S. Pat. No. 4,502,372 issued on Mar. 5, 1985 to Rene Mariotti for a Deep-Fryer Pan for Industrial Fryers and U.S. Pat. No. 4,505,193 issued on Mar. 19, 1985 to Rene Mariotti for an Industrial Deep-Fryer. Those early devices simply involved a check valve arrangement at each end of concentric flow paths for the oil. For a variety of reasons, that earlier design has not proved to be acceptable.
A later approach to such valve arrangements included the use of fluid actuated disk valves carried by a stem. In response to sufficient positive flow against gravity, the disk valves moved to a first position where fluid communication was permitted longitudinally through the assembly but lateral flow into the assembly was blocked. In a second position attained in response to gravity and negative flow, the disk valves blocked longitudinal flow through the assembly by permitted lateral flow into the assembly. An example of this type of valve assembly is illustrated in U.S. Ser. No. 927,401 of Rene Mariotti, filed Nov. 6, 1986 for a Flow Control Valve. With such an arrangement, the flow could not be adequately directed to auxiliary apparatus such as an oil heater. This particular valve exhibited some specific disadvantages: the valve did not work when there was a slow application of pressure; the valve did not provide an effective fluid seal.
The particular apparatus for which these flow control valves are intended is a vending machine for use in preparation of french fried potatoes. The vending machine application is fraught with a variety of problems which are not usually encountered in fluid control devices. For example, one problem which has plagued the earlier versions of these flow control valves is the difficulty in cleaning them. In food service applications, it is necessary that the flow control valves be adapted for easy disassembly so that the valves can be readily cleaned.
Another problem concerns reliability of operation. In food service applications, the control valve must exhibit a high level of reliability. That requirement is even further exacerbated when the control valve is to be used in an untended vending operation.
From these and other problems and deficiencies that will be apparent to those of ordinary skill in the art, it will be apparent that the need continues to exist for an improved control valve assembly which obviates those problems and deficiencies.